Semiconductor packages typically comprise an enclosed die that generates a certain amount of heat during operation. Some semiconductor dies are high power devices that generate a significant amount of heat, such as transient voltage suppressors. Cooling devices are often employed to facilitate the dissipation of thermal heat, such as heatsinks and the like. Typically, the semiconductor die is mechanically and thermally coupled to the heatsink, and may be joined thereto by a thin solder bond line.
Semiconductor die typically have a low coefficient of thermal expansion, such as silicon die. In contrast, heatsinks typically have a high thermal coefficient of thermal expansion as they typically comprise of metal materials. Thus, the materials expand at different rates as a function of temperature during operation which can crack and damage the die over varying operating temperatures. It is conventional in the industry to implement more expensive materials to thermally match and join the die to the high coefficient of thermal expansion materials. Typically, these thermal matching materials are interposed between the die and the thermal cooling member, such as the heatsink.
There is desired a less expensive high power surface mount package that eliminates the need for expensive thermal matching materials, and particularly a large surface area die having large surface areas.